Make fact available during puppet catalog compilation - puppet

Question

I have two classes in puppet.
Here is the first one:
class nagios::is_production {
file { '/etc/puppetlabs/facter/':
ensure => directory,
}
file { '/etc/puppetlabs/facter/facts.d/':
ensure => directory,
}
file { '/etc/puppetlabs/facter/facts.d/production.txt':
ensure => file,
content => epp('nagios/production.epp')
}
}
This creates a custom fact (production=yes/no based on the node name)
This class on its own assigns the fact correctly.
The second class:
class nagios::client {
if $facts[production] =~ yes {
##nagios_host {"${::hostname}":
ensure => present,
address => $::ipaddress,
hostgroups => "production, all-servers",
notifications_enabled => $notifications_enabled,
use => 'generic-server',
}
} else {
##nagios_host {"${::hostname}":
ensure => present,
address => $::ipaddress,
hostgroups => "non-production, all-servers",
notifications_enabled => $notifications_enabled,
owner => root,
use => 'generic-server',
}
}
}
This creates the exported resource for the host and adds it to either the production/non-production hostgroup.
If the custom fact exists, the host gets created with the hostgroup correctly.
I created a 3rd class to pull in these 2 just to keep track of it a little easier for myself:
class nagios::agent {
Class['nagios::is_production']->Class['nagios::client']
include nagios::is_production
include nagios::client
}
This seems like it should make ::is_production run before ::client. When I include this class on the node for the puppet run, I get this error:
Error: Could not retrieve catalog from remote server: Error 500 on SERVER: Server Error: Evaluation Error: Left match operand must result in a String value. Got an Undef Value. at /etc/puppetlabs/code/environments/production/modules/nagios/manifests/client.pp:3:6 on node
So the fact seems like it's not getting set causing the export of the host to fail.
What am I missing?
Followup to answer
I am trying to do this:
if domain name contains 'something'
production=yes
else
production=no
Then in the nagios module,
if $facts[production] =~ yes
Assign to production host group.
Bash:
#!/bin/bash
if [[ $(hostname) =~ '512' ]] ; then
echo production=yes
else
echo production=no
fi
Id like to be able to use $facts[something] in here to make create other facts based off things like OS and IP.
I read here: Custom Facts Walkthrough
But I wasn't able to understand the custom facts load path as I didn't have that directory. I'm very new to puppet...
Also new to stack overflow... did I do this right?
Thanks

Answer 1

Facts are generated during pluginsync. Since you are trying to place the external fact during catalog execution, it is not available earlier during catalog compilation, which occurs after pluginsync.
You need to remove your nagios::production class and place your external fact directly in the module to take advantage of pluginsync. It should be located in your module structure like this:
nagios
|__facts.d
|__production.txt
The external fact will then be copied over during pluginsync and the fact will be generated. It will then be available later during catalog compilation. Facter will expect your production.txt to be key:value pairs too.
Check here for more information on properly using external facts: https://docs.puppet.com/facter/3.5/custom_facts.html#external-facts